1. Field of the Invention
The present invention relates to a substrate processing apparatus for processing substrates, such as semiconductor wafers, by a predetermined process and a substrate processing method.
2. Description of the Related Art
A semiconductor device fabricating process employs a wafer cleaning apparatus that cleans semiconductor wafers, i.e., substrates, with a cleaning liquid, such as pure water or a desired chemical liquid, to clean the wafers of contaminants including organic contaminants and metallic impurities, and a wafer drying apparatus that removes liquid drops from wafers for drying by means of an inert gas, such as N2 gas, or a highly volatile and hydrophilic IPA vapor. Each of those known wafer cleaning apparatus and wafer drying apparatus is of a batch processing type that processes a plurality of semiconductor wafers simultaneously in a wafer cleaning chamber or a wafer drying chamber.
Batch-type wafer cleaning apparatus are disclosed in, for example, U.S. Pat. Nos. 5,784,797, 5,678,320 and 5,232,328. The batch-type wafer cleaning apparatus has a wafer carrying device that carries semiconductor wafers into a wafer cleaning chamber formed therein. Generally, the wafer carrying device has a wafer chuck including a pair of gripping members. The wafer chuck grips a plurality of semiconductor wafers collectively. A lateral rotor is supported for rotation in the wafer cleaning chamber. The plurality of semiconductor wafers carried into the wafer cleaning chamber by the wafer carrying device are held by holding members mounted on the rotor in the wafer cleaning chamber. More concretely, in the wafer cleaning apparatus disclosed in U.S. Pat. Nos. 5,784,797 and 5,678,320, the wafer chuck of a wafer carrying device is moved through a doorway formed in a front wall of a wafer cleaning chamber (a wall facing the wafer carrying device moving toward a wafer cleaning chamber) into the wafer cleaning chamber from a side in front of a wafer cleaning tank (from a side in front of the rotor), and wafers are transferred from the wafer chuck to the rotor.
A known wafer cleaning apparatus 400 shown in FIG. 32 has a wafer cleaning tank 402 defining a wafer cleaning chamber 401. A rotor 405 capable of holding semiconductor wafers W and of rotating can be moved through an opening 403 formed in the front end of the cleaning tank 402 into and out of the cleaning tank 402. With the rotor 405 disposed outside the wafer cleaning tank 402, the semiconductor wafers W are transferred between the rotor 405 and a chuck having gripping members 409a and 409b and attached to a carrying device. The rotor 405 is moved into and out of the cleaning tank 402 and is rotated by a driving mechanism 407. A shaft 480 is connected to the rotor 405.
A batch-type wafer drying apparatus is disclosed in, for example, JP-A No. Hei 6-112186. This prior art batch-type wafer drying apparatus has a wafer cleaning tank defining a wafer drying chamber and having an upper wall provided with a doorway. A lateral rotor is disposed in the wafer cleaning chamber. A wafer holding hand capable of vertical movement for handling semiconductor wafers is detachably mounted on the rotor. The wafer holding hand is raised through the doorway to a position above the wafer cleaning tank to transfer semiconductor wafers between the wafer holding hand and a wafer carrying device. When drying semiconductor wafers by this batch-type wafer drying apparatus, the semiconductor wafers are transferred from the wafer carrying device to the wafer holding hand and the wafer holding hand is lowered to place the wafers in the wafer drying chamber. Subsequently, the wafer holding hand holding the semiconductor wafers is mounted on the rotor to load the rotor with the wafers, and the wafers are dried. After the wafers have been dried, the wafer holding hand is separated from the rotor, is raised to a position above the wafer drying tank, and the dried wafers are griped by the wafer carrying device.
The wafer cleaning apparatus disclosed in U.S. Pat. Nos. 5,784,797 and 5,678,320 need to secure a space sufficient for the wafer chuck to operate in the wafer cleaning chamber and hence the size of the wafer cleaning chamber must be increased accordingly. Since the wafer chuck operates in a limited space in the wafer chamber, the operation of the wafer chuck must be carefully controlled so that the wafer chuck may not collide against the wall of the wafer cleaning tank. Consequently, the wafer carrying device must execute complicated operations and a control program for controlling the wafer carrying device is inevitably complicated.
Although the wafer chuck of the wafer cleaning apparatus 400 shown in FIG. 39 does not need to operate in a limited space, the wafer chuck must be controlled so that the gripping members 409a and 409b of the wafer chuck may not collide against the holding members 406 of the rotor 405. Consequently, a complicated control program is necessary for controlling the wafer chuck and the rotor 405.
In the wafer drying apparatus disclosed in JP-A No. Hei 6-112186, the wafer holding hand is always in contact with the semiconductor wafers throughout a period in which the wafers are carried into the drying chamber, dried and carried out of the drying chamber. Therefore, there is the possibility that particles and the like adhering to and remaining on the wafer holding hand adhere again to the wafers to contaminate the dried wafers.
Accordingly, it is an object of the present invention to provide a substrate processing apparatus having a small substrate processing chamber and facilitating work for carrying substrates into and out of the substrate processing chamber, and a substrate processing method. Another object of the present invention is to provide a substrate processing apparatus and a substrate processing method capable of preventing the contamination of substrates.
To achieve the objects, the present invention provides a substrate processing apparatus including: a substrate processing portion at which a plurality of substrates are treated by a process; a substrate waiting portion at which the substrates stand by for the process, the waiting portion being arranged below the processing portion; and a substrate lifter including a substrate supporting member configured to support the substrates from below the substrates, the supporting member being capable of vertical movement, wherein the lifter supports the substrates placed at the waiting portion and raises the substrates thereby moves the substrates from the waiting portion to the processing portion, and wherein the lifter supports the substrates placed in the processing portion and lowers the substrates thereby moves the substrates from the processing portion to the waiting portion.
The present invention also provides a substrate processing apparatus including: a substrate processing portion at which a plurality of substrates are-treated by a process; a substrate waiting portion at which the substrates stand by for the process, the waiting portion being arranged above the processing portion; and a substrate lifter including a substrate supporting member configured to support the substrates from below the substrates, the supporting member being capable of vertical movement, wherein the lifter supports the substrates placed at the waiting portion and lowers the substrates thereby moves the substrates from the waiting portion to the processing portion, and wherein the lifter supports the substrates placed in the processing portion and raises the substrates thereby moves the substrates from the processing portion to the waiting portion, and wherein the lifter is disposed outside of the processing portion.
According to another respect of the present invention, a substrate processing method is provided, the method including the steps of: carrying a substrate container containing a plurality of substrates into a container waiting portion disposed below a substrate processing portion for processing substrates; supporting the substrates contained in the substrate container, and raising the substrate to the processing portion disposed above the waiting portion; treating the substrates by a process at the substrate processing portion; supporting the substrates which have been treated and lowering the substrates into a substrate container; and carrying out the substrate container containing the processed substrates, which have been treated, from the waiting portion.
The present invention also provides a substrate processing method including the steps of: holding a plurality of substrates by an arm and carrying a substrates into a substrate waiting portion disposed above a substrate processing portion; delivering the substrates from the arm to a supporting member; lowering the supporting member thereby moving the substrates to the processing portion; holding the substrates by a substrate holding device provided at the processing portion; further lowering the supporting member thereby withdrawing the supporting member from the processing portion; and treating the substrates by a process at the substrate processing portion.